Skip to content
By using Twitter’s services you agree to our Cookies Use. We and our partners operate globally and use cookies, including for analytics, personalisation, and ads.
  • Home Home Home, current page.
  • About

Saved searches

  • Remove
  • In this conversation
    Verified accountProtected Tweets @
Suggested users
  • Verified accountProtected Tweets @
  • Verified accountProtected Tweets @
  • Language: English
    • Bahasa Indonesia
    • Bahasa Melayu
    • Català
    • Čeština
    • Dansk
    • Deutsch
    • English UK
    • Español
    • Filipino
    • Français
    • Hrvatski
    • Italiano
    • Magyar
    • Nederlands
    • Norsk
    • Polski
    • Português
    • Română
    • Slovenčina
    • Suomi
    • Svenska
    • Tiếng Việt
    • Türkçe
    • Ελληνικά
    • Български език
    • Русский
    • Српски
    • Українська мова
    • עִבְרִית
    • العربية
    • فارسی
    • मराठी
    • हिन्दी
    • বাংলা
    • ગુજરાતી
    • தமிழ்
    • ಕನ್ನಡ
    • ภาษาไทย
    • 한국어
    • 日本語
    • 简体中文
    • 繁體中文
  • Have an account? Log in
    Have an account?
    · Forgot password?

    New to Twitter?
    Sign up
GidMK's profile
Health Nerd
Health Nerd
Health Nerd
Verified account
@GidMK

Tweets

Health NerdVerified account

@GidMK

Epidemiologist. Writer (Guardian, Observer etc). "Well known research trouble-maker". PhDing at @UoW Host of @senscipod Email gidmk.healthnerd@gmail.com he/him

Sydney, New South Wales
theguardian.com/profile/gideon…
Joined November 2015

Tweets

  • © 2021 Twitter
  • About
  • Help Center
  • Terms
  • Privacy policy
  • Cookies
  • Ads info
Dismiss
Previous
Next

Go to a person's profile

Saved searches

  • Remove
  • In this conversation
    Verified accountProtected Tweets @
Suggested users
  • Verified accountProtected Tweets @
  • Verified accountProtected Tweets @

Promote this Tweet

Block

  • Tweet with a location

    You can add location information to your Tweets, such as your city or precise location, from the web and via third-party applications. You always have the option to delete your Tweet location history. Learn more

    Your lists

    Create a new list


    Under 100 characters, optional

    Privacy

    Copy link to Tweet

    Embed this Tweet

    Embed this Video

    Add this Tweet to your website by copying the code below. Learn more

    Add this video to your website by copying the code below. Learn more

    Hmm, there was a problem reaching the server.

    By embedding Twitter content in your website or app, you are agreeing to the Twitter Developer Agreement and Developer Policy.

    Preview

    Why you're seeing this ad

    Log in to Twitter

    · Forgot password?
    Don't have an account? Sign up »

    Sign up for Twitter

    Not on Twitter? Sign up, tune into the things you care about, and get updates as they happen.

    Sign up
    Have an account? Log in »

    Two-way (sending and receiving) short codes:

    Country Code For customers of
    United States 40404 (any)
    Canada 21212 (any)
    United Kingdom 86444 Vodafone, Orange, 3, O2
    Brazil 40404 Nextel, TIM
    Haiti 40404 Digicel, Voila
    Ireland 51210 Vodafone, O2
    India 53000 Bharti Airtel, Videocon, Reliance
    Indonesia 89887 AXIS, 3, Telkomsel, Indosat, XL Axiata
    Italy 4880804 Wind
    3424486444 Vodafone
    » See SMS short codes for other countries

    Confirmation

     

    Welcome home!

    This timeline is where you’ll spend most of your time, getting instant updates about what matters to you.

    Tweets not working for you?

    Hover over the profile pic and click the Following button to unfollow any account.

    Say a lot with a little

    When you see a Tweet you love, tap the heart — it lets the person who wrote it know you shared the love.

    Spread the word

    The fastest way to share someone else’s Tweet with your followers is with a Retweet. Tap the icon to send it instantly.

    Join the conversation

    Add your thoughts about any Tweet with a Reply. Find a topic you’re passionate about, and jump right in.

    Learn the latest

    Get instant insight into what people are talking about now.

    Get more of what you love

    Follow more accounts to get instant updates about topics you care about.

    Find what's happening

    See the latest conversations about any topic instantly.

    Never miss a Moment

    Catch up instantly on the best stories happening as they unfold.

    1. Anthony Cochrane‏ @m0102940 21 Sep 2020
      Replying to @ClareCraigPath @Pierssy @MattHancock

      1st the false positive rate is probably between 1 in 100 or 1 in 1000 (0.1-1%). So @GidMK is correct. What Clare is trying to say is based upon @carlheneghan paper which states that If you do lots & lots of tests in people with you create more false positives. 1/n

      2 replies 0 retweets 1 like
    2. Anthony Cochrane‏ @m0102940 21 Sep 2020
      Replying to @m0102940 @ClareCraigPath and

      For example - if you tested everyone in the world for Smallpox (now eradicated and thus impossible to actually have) with a test 99.999999% specific would would still get 7000 positive results.

      1 reply 0 retweets 1 like
    3. Anthony Cochrane‏ @m0102940 21 Sep 2020
      Replying to @m0102940 @ClareCraigPath and

      But if you test when something is common place you might underestimate it because test only picks up 70-80% of cases. So the higher infection levels the bigger the bigger the underestimate- whereas low infection levels tend to overestimate.

      3 replies 0 retweets 2 likes
    4. Health Nerd‏Verified account @GidMK 21 Sep 2020
      Replying to @m0102940 @ClareCraigPath and

      This is factually accurate, but as we usually test for COVID-19 in people that we are suspicious of having the disease (as opposed to a random sample a la ONS) the prevalence is quite substantially higher than the population prevalence

      2 replies 0 retweets 1 like
    5. Health Nerd‏Verified account @GidMK 21 Sep 2020
      Replying to @GidMK @m0102940 and

      Given the extremely high specificity of the test in operation (ONS estimates 99.92%+), to have a positive predictive value of only 50% we would need a population prevalence of <0.1% in the population tested (people being referred for tests)

      2 replies 0 retweets 1 like
    6. Dr Clare Craig‏ @ClareCraigPath 21 Sep 2020
      Replying to @GidMK @m0102940 and

      You can't prove that 99.92% figure. ONS can only hazard a guess.

      1 reply 0 retweets 0 likes
    7. Health Nerd‏Verified account @GidMK 21 Sep 2020
      Replying to @ClareCraigPath @m0102940 and

      It is the minimum POSSIBLE figure if every positive in their validation dataset was a false positive. The true number is likely closer to 100%, as seen in Australia, China, and Germany, but as the worst possible situation it is a useful example

      2 replies 0 retweets 1 like
    8. Health Nerd‏Verified account @GidMK 22 Sep 2020
      Replying to @GidMK @ClareCraigPath and

      In the first week of August the Australian state of NSW ran 150,000 tests and recorded 110 positives. In an absolute worst case scenario, where every positive was false, that implies a sensitivity of 0% and a specificity of ~99.94%

      2 replies 0 retweets 1 like
    9. Dr Clare Craig‏ @ClareCraigPath 22 Sep 2020
      Replying to @GidMK @m0102940 and

      False positives are not just a result of the testing process. They are also a function of the population being tested. Plus you can't take a minimum value - it will tend to a mean.

      1 reply 0 retweets 1 like
    10. Dr Clare Craig‏ @ClareCraigPath 22 Sep 2020
      Replying to @ClareCraigPath @GidMK and

      For example, if you imagined a population all infected with SARS1, you would expect them to have a higher false positive rate than a healthy population.

      1 reply 0 retweets 0 likes
      Health Nerd‏Verified account @GidMK 22 Sep 2020
      Replying to @ClareCraigPath @m0102940 and

      All of that being true, the observable - and demonstrable - false positive rate is roughly 1 per 2,000 true negatives, for a specificity of 99.95% or higher. Thus, you would only expect a PPV of 50% if the tested population had a prevalence of <0.1%

      1:28 AM - 22 Sep 2020
      • 1 Like
      • Pierssy 💙
      2 replies 0 retweets 1 like
        1. New conversation
        2. Health Nerd‏Verified account @GidMK 22 Sep 2020
          Replying to @GidMK @ClareCraigPath and

          (In this case, taking a minimum value is better for your argument. The true test specificity is likely to be ~99.99% or higher, which would make your original point wrong unless the prevalence was virtually 0%)

          1 reply 0 retweets 0 likes
        3. Dr Clare Craig‏ @ClareCraigPath 22 Sep 2020
          Replying to @GidMK @m0102940 and

          With a specificity of 99.95% then you would expect all of the summer ONS 'cases' to be false positive. Either that or you assume 100% specificity with R-value rock steady at 1.0000. Here is evidence so far that summer COVID was minimal -https://logicinthetimeofcovid.com/2020/09/07/waiting-for-zero/ …

          1 reply 0 retweets 0 likes
        4. Show replies
        1. Corona Realism  🟢‏ @holmenkollin 22 Sep 2020
          Replying to @GidMK @ClareCraigPath and

          Also in these „zerocovid“ regions we might have decreased sensitivity, so you really have to control if ct is the same (40) as everywhere else. Also cave: fp come in clusters (sloppy working labs with contamination issues), you might miss them in your reference samples

          0 replies 0 retweets 0 likes
          Thanks. Twitter will use this to make your timeline better. Undo
          Undo

      Loading seems to be taking a while.

      Twitter may be over capacity or experiencing a momentary hiccup. Try again or visit Twitter Status for more information.

        Promoted Tweet

        false

        • © 2021 Twitter
        • About
        • Help Center
        • Terms
        • Privacy policy
        • Cookies
        • Ads info